package com.atguigu.gulimall.product.service.impl;

import org.springframework.stereotype.Service;

import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;

import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    /**
     * 查询商品的三级分类
     * @return
     */
    @Override
    public List<CategoryEntity> listWithTree() {
        //1. 查出所有的分类
        List<CategoryEntity> list = baseMapper.selectList(null);
        //2. 组装成父子的树形结构
        //2.1 查询所有的一级分类
        List<CategoryEntity> leve1Menus = list.stream().filter((categoryEntity) -> {
            return categoryEntity.getParentCid() == 0;
        }).map((meun) -> {
            meun.setChildren(getChildrens(meun, list));
            return meun;
        }).sorted((meun1, menu2) -> {
            return meun1.getSort() - menu2.getSort();
        }).collect(Collectors.toList());

        return leve1Menus;
    }

    /**
     * 逻辑删除分类
     * @param asList
     */
    @Override
    public void removeMenuByIds(List<Long> asList) {
        //TODO 1. 检查当前删除的菜单，是否被别的地方引用
        // 使用逻辑删除
        baseMapper.deleteBatchIds(asList);
    }

    private List<CategoryEntity> getChildrens(CategoryEntity root, List<CategoryEntity> all) {
        List<CategoryEntity> children = all.stream().filter(categoryEntity -> {
            return categoryEntity.getParentCid() == root.getCatId();
        }).map(categoryEntity -> {
            categoryEntity.setChildren(getChildrens(categoryEntity, all));
            return categoryEntity;
        }).sorted((menu1, menu2) -> {
            return (menu1.getSort() == null ? 0 : menu1.getSort()) - (menu2.getSort() == null ? 0 : menu2.getSort());
        }).collect(Collectors.toList());
        return children;
    }

}